no signal

Yesterday Box on 1st tv stopped working, no lights at all on it, plugged in working power strip etc, outlet fine. 2nd tv No signal error..  Rebooted all, rechecked all,  cable is connected tightly, rechecked multiple times. Called xfinity and somehow got through after automated system saw errors. Agreed with live agent to go to store and get a new box and dvr because it also was having issues. I hooked up new equipment and box is lit etc but getting no signal errors. Cables are connected fine, rechecked multiple times.. Automated system keeps telling me it needs to do a restart but then it tells me it cannot restart. When I call automated  system it keeps asking about my modem. Modem is FINE. No matter what I try  it puts me in a loop. I try to make an appt online for a technician and it also will not let me until the restart goes through. I am not happy. How in the world do I with a technician or make appt.